Is this good for my first scope?

[astrogeek (Leon)]

A good society is the Astronomical Society of Victoria. It is the biggest in the southern hemisphere and a great society. I have been a member for about four years now. There is a wide variety of speciallised groups within the society for those interested. They also have a dark sky site about 1 1/2 to 2 hours drive from melbourne. For more info go to:

www.asv.org.au

Leon

[Ziggy Stardust]

for my two cents...

my first scope waited a full year extra, so I could get something good. I started with the Bino's and learn to find stars and systems first, then after a year of looking and saving, got me a shop demo. It was a Helois (also called Skywatcher insome markets) 6 inch scope.
The old girl is still in my collection and is one of my favourite toys, as she is big and collects lots of light, but still easy to cart around in a car! All I did do was put some extra meat around the sliding joints and beef up the thumb screws with new SS ones. Because my first scope was agood quality scope, I had many enjoyable nights and days ( doing solar work). Many times I have seen guys rush off and buy cheap and cry all night, So if you got $200 now,,, save a few months till you got $600~$900... then you can get something great.

These days I use my big Meade, the Helois and the Borge at most meetings. each has it own target area that it excels at.... be that planets, the moon or the deep sky fuzzyball...
Also i found that once I started to use 2inch eye peaces on the 6inch refractor, it came out in full bloom and showed me what it could really do!!!!


Tony

[mickoking]

Originally Posted by Striker

And shipping shouldn't be too much from Andrews...I ordered a 8" dob and only cost me $50 postage 1 year ago....from Sydney to Brisbane.

I orderd a 250 mm Dob and the postage to Perth was $90-.

[janoskiss (Steve H)]

Originally Posted by mickoking

Speak for your self my synta is heaps better than my Guan sheng.

"Heaps better"? What's wrong with your GS? And what's so much better about the Synta? Please, tell us more!

(BTW: The ED80 was the first thing to pop into my head when I read Ken's comment. But just cos they made a good refractor does not nec mean they make good reflectors... )

[iceman (Mike)]

I'm sure it's a quite open debate.. it depends who you talk to.

Some will say the skywatcher (synta) dobs are better than GSO, others will say the opposite.

But in any case, there's not a lot of difference in it so I certainly don't think you could say either of them are "only ok".

Unfortunately you won't find many people who have owned both, in order to have done a side by side.

[Roger Davis]

Synta or Guan Sheng, optically there is not much difference. Both fall into the category of delivering images to the eye which have a wavefront that does not give blurry images. Wavefront error for both is less than 1/8th of a wave of sodium light (seen them as good as 1/10th) that's after primary and secondary reflection. Test done using Foucault and Ronchi tests, as well as comparison of stars as per "Star Testing Astronomical Telescopes" by **** Suiter. (Also see ATM Journal article on what the eye can see with verious wavefront errors.)
The difference lies in the side bearings. Synta with the handles and Guan Sheng with the springs.
Both have their disadvantages.
The GS Spring was a *******isation of an invention that appeared in the Amateur Telescope Makers Journal or Magazine, about controlling the balance of a Dob with tangential pressure on the altitude bearing by using a spring. The GS one is nothing like that which was proposed! It does work in a fashion, but not as per the intention of the original designer. A tangential control gives EVEN control over the entire 90° of travel in altitude.
The handles on the Synta have their problems too. There is a small ball bearing thrust washer on the handle closest to the observer that bears against another threaded washer onto the side of the rocker box. Through overtightening or constant adjustment (even disassembling and reassembling) the threaded washer can lose its thread and fall off, leaving you with a hand full of ball bearings (fixed a couple now). The tension from this handle can also distort the rocker box side, giving a non-orthogonal bearing. Not so good for DSC's.
So take your pick, one is just as bad as the other.

[Roger Davis]

What is this? **** The gentlemans name is Richard and he wants to be known as **** but the word **** is being removed due to its other conotation. The word *******ise is a perfectly good term referring to the misuse of a principle, not a person born out of wedlock.
Isn't this censorship going too far?

[iceman (Mike)]

The "naughty word filters" have been in place for over 12 months, and haven't had a review. The moderators and I have been discussing which words should and shouldn't be censored, and the discussion is ongoing.

This is a family friend forum, it's a fine balance between allowing a word calling someone by their preferred name, and allowing a word where it could be used in other fashions. Yes it's censorship. Is it going too far? I don't think so.

Anyway, it's off-topic to this thread. If you've got ideas or suggestions, please email or PM me, or start a discussion on it in the website feedback forum.

[janoskiss (Steve H)]

hehehe. Roger, Thanks for the wealth of info on the two types of Dobs! Yes those springs are better than nothing, but I don't like them. I prefer to use counterweights for balance instead and have the same amount of force required to move up & down. The friction on the my GS altitude bearings is still not great though, even when the scope's balanced. The laminate I got for the base is too stiff to bend around the bearings. The tinkering never ends...

You learn to live with the word filter after a while. You can drink & drive here and no one can call you nasty names like the TAC would. Friendly place this.